andrew wrote:
Anyone got any ideas for sending a pulse to a 24V relay via an opto isolator
plugged into a USB port, this is to open a security gate some 150 metres
away.

The obvious way would be using something like the DTR line on a USB to
RS232 adaptor. 99p on ebay usually.

Alternatively a remote single board PC with IO capability communicating
with the main host over a homeplug network connection.


--
Cheers,

John.

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